Stackers and hopper-loaders commonly have sheets standing on edge, such as shown in the stacker patents U.S. Pat. Nos. 2,841,394 and 2,933,313. In both of those instances, a stack of sheets is being formed from an incoming stream of sheets, and there is required a movable backstop supporting the forward or advancing end of the stack. That backstop must be manually positioned by an operator, and also eventually removed when the stack itself is to be maneuvered.
One skilled in the art is also aware of positioning, in a hopper-loader, a bundle or stack of sheets which stand on their edges and which are advanced forward into a sheet-feeding presentation in the feeder itself. In that instance, it is commonly known that a backstop must again be employed for supporting the sheets in their edge-standing or generally upright position, and for advancing those sheets in the hopper-loader. Again, that requires the provision of a backstop and also the maneuvering of the backstop by an operator.
The present invention improves upon the prior art in that it employs means on the opposite sides of otherwise freestanding sheets in a stack or bundle, all to prevent the sheets from falling forward or backward and thereby moving out of the standing position in the bundle. The invention herein is accomplished by means of side supports for the bundle of sheets, which sufficiently engage the sheets, such as by either spring action or embedding of brush bristles or the like toward and between the sheets, or by a jagged or serrated type of edge which will engage the opposite sides of the sheets and prevent them from falling forward or backward However, the prior art is also aware of the utilization of brushes for controlling the edges of sheets, but only on the bottom of the sheets, rather than on opposite sides as in this invention. An example of that type of prior art is found in U.S. Pat. No. 3,718,217 where a bottom brush is utilized, though that brush is only for the retardation of the sheets, rather than supporting the sheets in their upstanding position, as in the present invention.
The present invention therefore provides apparatus which conveniently and in simplified manner supports a bundle of sheets in an upstanding position, by supporting the opposite sides of the sheets, and the support means itself can either be a stationary brush or serrated member or it can be of that construction but movable in the direction of the desired advancement of the bundle or stack of sheets.